Thinning paints with thinners

G'day all,

I've painted a bit of mild steel with a hammertone paint today and after all the things I've ever painted with oil based paints I think today I've just discovered that thinning oil based paints with thinners is disaster!

I did my first coat with the same paint thinned with turps and the finish was nice, you could glide your fingers along the metal and it felt like there was a good coverage and it felt glossy. I did the second coat with the same paint again but this time thinned with thinners. The coats seemed to come out of the gun OK but didn't look like it was looking as good on top of the other coat. Once finished (dried) it felt like it was very thin and a dry rough feel, so looks like I need to give it another coat now - sort of spewing as I was hoping to get away with 2..... I think I may just use the thinners for cleaning purposes only from this day on and thin oil based paints from now on with the turps.

Anybody that is experienced share this view - or can tell me that I should never have used thinners in the first place?

Geoff

I've read the same thing (in relation to epoxy enamels).

Don't know why, but it may have something to do with the rate of evaporation i.e the thinners evaporates before the paint flows out and smooths.

Now I am no expert on this but was yarning to a colleague recently about general purpose thinners and enamel paints. This guy has done his share of spray painting and told me that general purpose thinners are vegetable (tobacco) based with additives and not suitable for enamel paints.

Gary

Paint thinners will flash off very quickly (minutes) compared to turpentine. Premium (not general purpose) thinners used for automotive topcoats have a slightly longer flash off time compared to GP thinners, but it's still lightning fast compared to turps.

You also have to be careful to use the right thinners with hammertone paints - too much, or the wrong stuff, can cause the flake to settle or strange things to happen to the hammer effect; and don't forget to clean the gun well, as hammertone paints use silicone (gives the hammer effect) which can be a pain when it gets into your normal paint.

And I think you'll find that the closest that thinners have been to a vegetable origin was as plankton way back in the Jurassic....(however, when smoking you do get to inhale some of the same nasty long-named compounds as found in thinners).

I've no idea what your Hammertone paint is but it sounds remarkably like our Hammerite.

For that the thinners is Xylene, not impossible to get these days, but not altogether easy either.